How do I know if my Tiffany style lamp is real?

Most lamps called "Tiffany" are Tiffany-style, made by many companies from the 1970s on, and they are decorative pieces that usually sell for modest amounts. Genuine Tiffany Studios lamps were made in New York in the late 1800s and early 1900s and are among the most faked American antiques, so careful checking is needed.

Real Tiffany shades are usually marked on a small metal tag or stamped on the inside rim, and the bases are marked on the underside with "Tiffany Studios New York" and often a model number. But marks are easy to fake, so experts look at more: the quality and richness of the glass, which often has texture, ripples or streaks of color, the fine copper foil work and patina, the weight and quality of the bronze base, and how shade and base fit.

Overly bright, uniform glass, light bases and shiny new metal are warning signs. If you think yours may be genuine, do not clean or rewire it yet. Photograph the markings and have it seen by an auction company or appraiser that specializes in lighting or decorative arts.